Heat Sink For Electronic Components of a Rotating Electric Machine

ABSTRACT

A dissipator for discharging heat from electronic components, the electronic components being intended for the functioning of a rotary electrical machine, the rotary electrical machine comprising a rear bearing, the dissipator comprising a top face and a bottom face integrating fins, wherein the dissipator is disposed between the rear bearing of the rotary electric machine and the electronic components, the bottom face integrating the fins coming opposite the rear bearing when the dissipator is disposed between the rear bearing of the rotary electrical machine and the electronic components.

FIELD OF THE INVENTION

The invention concerns a dissipator for electronic components, the said electronic components being intended for the functioning of a rotary electrical machine, the said machine comprising a rear bearing, the said dissipator comprising a top face and a bottom face including fins.

The present invention applies to any type of polyphase rotary electrical machine, synchronous or asynchronous, such as alternators or alternator starters, and also whether it is a case of electrical machines for motor vehicles and driven for example by belt, with cooling by air, liquid or any other solution that can be envisaged.

BACKGROUND OF THE INVENTION

In a motor vehicle comprising a thermal engine and a rotary electrical machine such as an alternator starter, such an electrical machine comprises for example, non-limitatively:

a rotor comprising a field winding into which an excitation current is brought, and

a stator comprising a polyphase winding.

The alternator starter functions in motor mode or in generator mode. It is a so-called reversible machine.

In generator or alternator mode, the machine converts a rotation movement of the rotor driven by the thermal engine of the vehicle into an electric current induced in the phases of the stator. In this case, a bridge rectifier connected to the phases of the stator rectifies the sinusoidal induced current into a DC current in order to supply consumers on the vehicle such as a battery.

On the other hand, in motor mode, the electric machine serves as an electric motor for rotating, via the shaft of the rotor, the thermal engine of the vehicle. It converts electrical energy into mechanical energy. In this case, an inverter converts a DC current coming from the battery into an alternating current for supplying the phases of the stator in order to rotate the rotor.

Control signals are used to determine the operating mode of the rotary electrical machine (motor mode or generator mode).

In the document DE 102004007395 A1, the use is known of an external peripheral band, the said band comprising internal partitions including:

signal interconnection tracks for the transmission/reception of signals to the electronic components from the bridge rectifier/inverter, and

power interconnection tracks for connecting the electronic components to the battery so as to supply them,

all the tracks being superimposed on one another and being overmoulded. The band is positioned on the rear bearing of the machine. In addition, a dissipator is positioned above the said band.

One of the problems of such a solution is that there exists solely an air flow blown by the fan of the rotary electrical machine for cooling in particular the said machine and the electronic components, the said air flow being an axial air flow. This single air flow may be insufficient to allow effective cooling.

SUMMARY OF THE INVENTION

Thus an object of the present invention is to propose a dissipator for electronic components, the said electronic components being intended for the functioning of a rotary electrical machine, the said machine comprising a rear bearing, the said dissipator comprising a top face and a bottom face including fins, which makes it possible to more effectively cool the assembly consisting of rotary electrical machine and electronic components.

To this end, according to a first object of the present invention, the dissipator is disposed between the rear bearing of the said machine and the said electronic components, the said rear face including the said fins coming opposite the said rear bearing.

Thus, as will be seen in detail below, this specific arrangement of the dissipator makes it possible to obtain an additional radial flow that will also be blown by the fan of the machine and which, added to a blown axial flow, will increase the cooling of the machine and electronic components.

According to non-limitative preferential embodiments, the dissipator that is the object of the invention has the additional characteristics set out below.

The dissipator has a protrusion on its bottom face level with the fins.

The protrusion has a first slope for guiding an axial air flow towards the inside of the machine and a second slope for guiding a radial air flow towards the inside of the machine.

The dissipator has a spacing configured so as to allow air to pass around the rotor shaft of the machine.

The spacing is wider than the diameter of the rotor shaft.

A power interconnection piece (21) is placed on the bottom face of the dissipator, the said power piece distributing power to the said module.

At least one electronic module comprising electronic components is mounted on the top face of the said dissipator.

A signal interconnection piece is mounted on the said electronic module, the said signal interconnection piece being intended to convey control signals between electronic components.

The dissipator is attached.

Other characteristics and advantages of the present invention will emerge from the following description. This is purely illustrative and must be read with regard to the accompanying drawings, given by way of non-limitative examples.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a depicts the first embodiment of an electronic module according to the invention,

FIG. 1 b depicts the module of FIG. 1 a in a view from below,

FIG. 1 c is a view without overmoulding of the module of FIG. 1 a,

FIG. 1 d is the view of FIG. 1 c with hard-wired connections of the electronic components of the electronic module,

FIG. 2 a is a first variant of the first embodiment of FIG. 1 a,

FIG. 2 b is a view from below of the module of FIG. 2 a,

FIG. 2 c is the view of FIG. 2 a with hard-wired connections of the electronic components of the electronic module,

FIG. 2 d is a second variant of the first embodiment of FIG. 2 a,

FIG. 3 a shows a second embodiment of an electronic module according to the invention,

FIG. 3 b is a view from below of the module of FIG. 3 a,

FIG. 3 c is a view without overmoulding of the module of FIG. 3 a,

FIG. 3 d is a variant of the second embodiment of FIG. 3 a,

FIG. 3 e is the view of FIG. 3 d with hard-wired connections of the electronic components of the electronic module,

FIG. 4 a is a third embodiment of the electronic module according to the invention,

FIG. 4 b is a view from below of the module of FIG. 4 a,

FIG. 4 c is a view without overmoulding of the module of FIG. 4 a,

FIG. 4 d is a view in section without overmoulding of the module of FIG. 4 a including a support plate,

FIG. 4 e is the view of FIG. 4 c with hard-wired connections of the electronic components of the electronic module,

FIG. 5 a is a variant of the third embodiment of FIG. 4 a,

FIG. 5 b is a view from below of the module of FIG. 5 a,

FIG. 5 c is a first view from above without overmoulding of the module of FIG. 5 a,

FIG. 5 d is a second view from below without overmoulding of the module of FIG. 5 a,

FIG. 5 e is a third view from above without pre-moulding and without overmoulding of the module of FIG. 5 a,

FIG. 5 f is a fourth view from below without pre-moulding and without overmoulding of the module of FIG. 5 b,

FIG. 6 depicts a first embodiment of a dissipator bearing intended to receive a module of FIGS. 1 and 2,

FIG. 7 depicts a second embodiment of a dissipator bearing intended to receive a module of FIG. 3,

FIG. 8 a depicts a first embodiment of a dissipator intended to receive a module of FIGS. 4 and 5,

FIG. 8 b is a view from below of the dissipator of FIG. 8 a,

FIG. 8 c is a view in section of FIG. 8 b,

FIG. 8 d shows an axial air flow and a radial air flow in the dissipator of FIG. 8 b,

FIG. 9 a depicts a first embodiment of a signal interconnection piece intended to be placed on a module of FIGS. 1 and 2,

FIG. 9 b is a view from below of the piece of FIG. 9 a,

FIG. 9 c is a view without overmoulding of the piece of FIG. 9 a,

FIG. 10 a depicts a second embodiment of a signal interconnection piece intended to be placed on a module of FIG. 3,

FIG. 10 b is a view from below of the signal interconnection piece of FIG. 10 a,

FIG. 10 c is a view without overmoulding of the signal interconnection piece of FIG. 10 a,

FIG. 11 a depicts a third embodiment of a signal interconnection piece intended to be placed on a module of FIGS. 4 and 5,

FIG. 11 b is a view from below of the signal interconnection piece of FIG. 1 a,

FIG. 11 c is another view from above of the signal interconnection piece of FIG. 11 a,

FIG. 11 d is a view without overmoulding of the signal interconnection piece of FIG. 11 a,

FIG. 12 a shows a first embodiment of a power interconnection piece intended to be in contact with a module of FIGS. 1 and 2 and to be situated above the signal interconnection piece of FIG. 9,

FIG. 12 b is a view from below of the piece of FIG. 12 a,

FIG. 12 c is a view without overmoulding of the piece of FIG. 12 a,

FIG. 13 a depicts a second embodiment of a power interconnection piece intended to be in contact with a module of FIG. 3 and to be situated above the signal interconnection piece of FIG. 10,

FIG. 13 b is a view from below of the piece of FIG. 13 a,

FIG. 13 c is a view without overmoulding of the piece of FIG. 13 a,

FIG. 14 a shows a third embodiment of a power interconnection piece intended to receive a dissipator of FIG. 8,

FIG. 14 b is a view from below of the piece of FIG. 14 a,

FIG. 14 c is a view without overmoulding of the piece of FIG. 14 a,

FIG. 14 d is a view of the piece of FIG. 14 a including a collar,

FIG. 14 e is a view of the piece of FIG. 14 d on a dissipator bearing,

FIG. 15 a is a first embodiment of a cover intended to be situated on top of the power piece of FIG. 12,

FIG. 15 b is a view from above of the cover of FIG. 15 a,

FIG. 15 c is a side view of the cover of FIG. 15 a,

FIG. 16 is a second embodiment of a cover intended to be situated above the power piece of FIG. 13,

FIG. 17 a is a third embodiment of a cover intended to be situated on top of the signal interconnection piece of FIG. 11,

FIG. 17 b is a view from above of the cover of FIG. 17 a,

FIG. 18 depicts a mounting of an electronic module of FIGS. 1 and 2 on a dissipator bearing,

FIG. 19 depicts a mounting of a signal interconnection piece of FIG. 9 on the dissipator bearing/modules assembly of FIG. 18,

FIG. 20 depicts a mounting of the power interconnection part of FIG. 12 on the dissipator bearing/module/signal interconnection piece assembly of FIG. 19,

FIG. 21 depicts the arrangement of FIG. 20 with a cover in partial cross-section,

FIG. 22 is a complete view of the arrangement according to FIG. 21 with the cover in place, showing a positioning of the cover with respect to a module,

FIG. 23 depicts a mounting of an electronic module of FIG. 3 on a dissipator bearing,

FIG. 24 depicts a mounting of the signal interconnection part of FIG. 10 on the dissipator bearing/modules assembly of FIG. 23,

FIG. 25 depicts a mounting of the power interconnection part of FIG. 12 on the dissipator bearing/module/signal interconnection piece assembly of FIG. 24,

FIG. 26 depicts the arrangement of FIG. 25 with a cover in partial cross-section,

FIG. 27 a depicts a mounting of the modules of FIG. 4 on a dissipator,

FIG. 27 b depicts a mounting of the power interconnection piece of FIG. 14 on a dissipator,

FIG. 28 depicts a mounting of the power interconnection piece of FIG. 14 on the dissipator/modules assembly of FIG. 27 a,

FIG. 29 depicts a mounting of the signal interconnection piece on the assembly of FIG. 28,

FIG. 30 a is an assembling of the assembly of FIG. 29 on a bearing,

FIG. 30 b is a section along a plane X-Y of FIG. 30 a of the assembled power interconnection piece of FIG. 14 a, and

FIG. 30 c depicts a bearing on which the assembly of FIG. 29 is assembled.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

It should be noted that, in the remainder of the description, the diameter of a bearing of the machine without fixing lug is defined as the outside diameter of the machine.

Electronic Module

It should be noted that an electronic module, in the context of the invention, is a set of electronic components that are disposed in a housing and comprises connection elements accessible from the outside for its functioning, these elements making it possible to transmit control and/or power signals.

FIG. 1 a depicts a first non-limitative embodiment of an electronic module 10 according to the invention.

The said module 10 comprises:

a housing 101,

electronic components 102 located in a central zone 1021 covered with a protective gel such as a gel of the silicone or epoxy resin type, and a protective plastic cover,

electrical conductors 103 (B+), 104 (B−),

signal connection elements 106, and

fixing points 108.

In addition, the said module 10 comprises, as indicated on the view from below in FIG. 1 b:

means 109 of positioning the module 10 on a dissipator bearing.

The various elements of the said module 10 are described below.

The housing 101 is made from electrically insulating material. Preferably, the housing has a substantially triangular basic shape and therefore has at least three lateral faces and one top face and one bottom face. This shape will make it possible to use a maximum amount of surface area on the cylindrical rear of the machine, and this in an optimum fashion.

Moreover, preferentially, one of the faces of the module 10 is an arc of a circle. This is appropriate to the general shape of the machine.

Naturally it would be possible to use other shapes, such as a substantially rectangular shape.

The electrical power supply conductors 103 (B+), 104 (B−) convey a current coming from the battery through the electronic elements.

In a preferential embodiment, the conductors are two power connection tracks 103, 104, the ends of which are disposed on the external periphery of the module. Preferentially, the said tracks are made from copper.

Thus, unlike an architecture in which the power necessary for each module passes through all the modules or in which an electronic power card is situated in a housing separate from the machine, this configuration has the following advantages:

this allows a salt spray to flow towards the outside of the machine instead of banking up at the centre of the said machine, which prevents corrosion of the tracks by the said salt spray,

there is less heating in the modules since the power necessary for a module passes only through the said module,

the welds on the ends of the tracks are carried out on a single radius, which makes it possible to automate the welding better,

this also allows balancing of the current in the modules because each module is supplied independently, i.e. they are supplied in parallel.

In a first variant of this embodiment, the power tracks 103, 104 extend in a plane parallel to that along which the block of electronic elements extends. This allows laser welding axial with respect to the axis of the machine.

In a second variant, the tracks extend along two planes parallel to each other and parallel to the plane of the block of electronic elements.

It should be noted that track means a cropped metal sheet formed from a metal such as copper.

The signal connection elements 106, called signal connections, convey control signals for controlling the electronic elements 102. They thus allow the sending and reception of information necessary for controlling the inverter arm (motor mode) and/or the arm of the bridge rectifier (generator mode). They afford connection with a signal plate (described below).

In a first preferential embodiment, these signal connections 106 comprise a first series of tongues 106 a and are aligned on one of the lateral faces of the triangular housing of the module. Thus the axes of these signal connection elements 106 a are in the same plane P1 perpendicular to the bottom face of the module, the said plane passing essentially through the rotor rotation axis AX.

This alignment makes it possible to carry out linear tongue welding, which limits the time needed for the manufacturing method, called the “process”, and the size. This configuration has the advantage of having, for the signal interconnection piece, a signal track cut in one go, unlike another configuration in which the signal tracks overlap. It will be noted that, if the tongues are offset towards the inside of the module, i.e. if the plane does not pass through the rotation axis, the space for the electronic components 102 is reduced, and otherwise the space for the other modules is reduced.

Fixing means 108, represented here by orifices, are intended to facilitate the holding of the module on the electrical machine by means of studs 113 or screws etc, or any appropriate fixing means.

The means 109 of positioning the module 10 on a dissipator bearing or dissipator are here two in number 109 a, 109 b as illustrated in FIG. 1 b, which are on the bottom face of the module, close to two opposite edges. In the example, these are pins situated on each side of the electronic elements 102. They are here spaced at a maximum, which limits positioning errors.

In addition, preferentially, the module 10 also comprises, as illustrated in FIG. 2 a:

Means 107 of protecting the signal connections 106, facilitating the positioning of a cover (described below).

In addition, preferentially, the said electronic module 10 also comprises, as illustrated in FIG. 1 a:

A phase track 105 connecting the said module to a phase of the stator.

In a preferential embodiment, the phase track 105 has an end 105 z that comprises a hook 105 cr and makes it possible to connect thereto, by welding, brazing or any other suitable method, a phase wire or phase tongue coming from the stator of the electrical machine. In the example depicted in FIG. 1 a, the said end 105 z is perpendicular to the said track, i.e. to the bottom face, and is situated below the said plane; it extends downwards. Thus this allows a reduction in the length of the phase wire of the stator and involves a radial weld. In addition, the end 105 z of the phase track 105 is situated on the external circumference of the module, which facilitates the connection with a phase of the stator. In addition, preferentially, the end 105 z of the phase track 105 is placed between two electrical power conductors 103, 104.

This optimises the “wire bounding” hard-wired electrical connections between the transistor electronic components and the tracks, in particular their length, and this makes it possible to avoid overlapping of tracks. In addition, preferentially, the end of the phase track 105 is situated in line with a phase output of the stator, which facilitates the welding with the said phase.

In addition, preferentially, according to a first variant of this embodiment, the said electronic module 10 is a control module 30 that also comprises, as illustrated in FIGS. 2 a and 2 b:

A third series of signal tongues 106 c that are aligned on the external periphery of the triangular housing of the module, the said periphery coinciding with the outside diameter of the machine. This series of tongues makes it possible to be connected to a signal connector integrated in a cover.

A second series of tongues 106 b that are aligned parallel to the third series 106 c and offset towards the inside of the module. This second series of tongues conveys complementary signals that have not been able to be integrated in the first series of tongues 106 a, for example signals SC for a control element of a switch. This enables the two series of tongues 106 b and 106 c to be cropped on a single occasion. It should be noted that the third series of tongues 106 c is preferentially positioned higher than the second series 106 b in order to facilitate the welding of a cover to the control module after having carried out the welding of a signal interconnection piece.

In other words, the second and third series of signal connections 106 b, 106 c are aligned on the same face on which the ends of the power connections are disposed.

a housing 112 for stator position sensors.

It should be noted that the interconnections between the transistors and the associated tracks are effected by “wire bounding” hard-wired connections as illustrated in FIG. 2 c. In the context of a module with a single transistor per potential, there is one transistor disposed on the positive track 103, which is connected to the phase track 105 and to the ceramic 1110 of the driver 111, while a second transistor is disposed on the phase track 105 and is connected to the negative track 104 and also to the ceramic 1110. It should be noted that it would also be possible to have a transistor on the negative track 104.

It should be noted that, in this example, there are four transistors, two transistors for the “low side”, indicated LS, and “high side”, indicated HS, of an arm, that is to say two transistors per potential in order to increase the power of the machine.

In addition, preferentially, according to a second variant of this embodiment, the said electronic module 10 is an excitation module 40, as illustrated in FIG. 2 d. It comprises electronic components 102, in particular MOS transistors and diodes, which represent the excitation stage of the rotor of the machine.

Thus the electronic modules 10 have, with regard to the arrangement of the tracks 103, 104 and their ends forming electrical conductors inside each module and with regard to the arrangement of the signal connections 106, a standardised architecture makes it possible to use the said modules on different types of electrical machine. This standardisation of the architecture makes it possible to replace any module 10 with a module with the same architecture. In addition, this makes it possible to integrate the said modules directly on the rear bearing of the machine. In this way the power and control electronics are integrated on the machine directly. The electronics are no longer in an electronic power card in a separate housing.

Thus, according to the architecture of an electronic module 10 described previously, it is possible to have power modules 20 (FIGS. 1 a to 1 c), a control module 30 (FIGS. 2 a to 2 c) and an excitation module 40 (FIG. 2 d).

In the case of the power modules 20, the electronic components 102, illustrated in FIG. 1 c, comprise for example:

a set of electronic switches 110 intended to produce a rectifier bridge/inverter arm for a phase of the machine,

control elements 111, called drivers, associated with the switches, and

a temperature sensor 118 (positioned on a ceramic) for the phase track 105.

The switches can for example be MOSFET-technology transistors 110 that are in the form of packaged components, that is to say presented with a can, or, in order to increase the compactness of the arrangement of the modules and to reduce costs, in the form of bare chips, that is to say without a can. The MOSFETs 110 are controlled by the control elements 111, normally called drivers, on a ceramic 1110 with additional components. Preferentially, the drivers are ASICs. The electronic elements can also be diodes of an arm of a bridge rectifier, since MOSs have a better efficiency than diodes. The number of electronic components depends essentially on the constraints of the particular application (three-phase or hexaphase machine for example), the level of power required by the machine, etc.

For a three-phase machine, there will preferably be three power modules serving to produce an inverter (one module per phase). More generally, the machine is a polyphase machine (x phases), preferably having one module per phase.

FIG. 1 d illustrates the hard-wired connections, normally referred to as “wire bounding”, between the transistors and the power connections 104 and the phase connections 105. It should be noted that, in this example, there exist four MOS transistors, so as to increase the power of the machine. Naturally there may be only two of them. It should be noted that the ceramic 1110 also serves as a support for electronic components but also as interconnection between the transistors and the driver 111.

The control module 30 makes it possible to control the machine and in particular the adjustment of the excitation current by controlling the drivers of the MOS transistors. It also has, as illustrated in FIG. 2 a, an electronic control component 102CTRL, capacitors 102CA and a transformer 102TR for supplying the drivers 111 of the power modules. Control signals will thus be sent from the control component 102CTRL to the drivers 111 of the power modules.

The excitation module 40 makes it possible to supply the coil of the rotor of the said machine, the said module comprising in a conventional manner MOS transistors and diodes for determining the current in the rotor.

Thus the control module 30 and the excitation module 40 repeat the architecture of the power modules 10 and in particular the arrangement of the ends of the power tracks 103, 104 and the signal connections 106.

According to a variant embodiment, the control module 30 and the excitation module 40 can be replaced by a common excitation and control module.

All the modules 20, 30 and 40 are mounted on a rear bearing of the rotary electrical machine.

In a second non-limitative embodiment, illustrated in FIG. 3 a, the electronic module 10 differs from the first embodiment in that:

in place of the fixing means 108, it has support zones 114 for receiving stays belonging to a signal interconnection piece, as will be described below, which makes it possible to omit the fixing studs 113 so that the cost of the parts and assembly are reduced, and this makes it possible to obtain a simpler assembly.

The novel module 10 can be seen in view from below in FIG. 3 b and in a view without overmoulding in FIG. 3 c for a power module. It should simply be noted in FIG. 3 b that the module preferably comprises a fixing clip 125 for a plastic cover for a module in order to protect the protective gel for the components. This fixing clip can be replaced by a bonding of the cover or ultrasonic welding for example.

FIG. 3 d presents a variant embodiment for a control/excitation module 30/40. It should be noted that having a single module for the control and excitation function makes it possible to save in terms of size.

FIG. 3 e presents the “wire bounding” hard-wired connections of this variant. It should be noted that there exists an interconnection between the control ceramic and the excitation ceramic (substrate) produced by a “wire bounding” hard-wired connection to allow transmission of signals between the excitation part and the control part.

In the first two embodiments described, preferentially, the ends of the said power tracks 103, 104 are flat and flush on the bottom face of the said module. Thus this configuration has the advantage of being able to weld tracks of a power plate (described in detail below) on the ends of tracks of a module by transparency (flat on flat).

In a third non-limitative embodiment, illustrated in FIG. 4 a, the electronic module 10 is configured so as to be fixed to a dissipator, itself fixed to the rear bearing of the machine.

It differs from the second embodiment in that:

the end 105 z of the phase track 105 is perpendicular to the bottom face of the module and projects beyond the housing 101 of the module and its plastic cover, and extends upwards. Thus this allows axial welding and thus prevents being interfered with by the lugs fixing the alternator starter on the engine, whatever the engine of a manufacturer; and this facilitates access to the welding tool,

the end of the positive track 103 (B+) is a folded tongue allowing radial laser welding with a power plate or axial electric welding by electrodes; it extends axially upwards with respect to the housing 101 of the module and projects beyond the said housing in order to engage the said electrodes, i.e. it is perpendicular to the bottom face of the module; the tongue projects beyond the dissipator. This makes it possible to connect a power interconnection piece 21 with the module from below,

the end of the negative track 104 (B−) is no longer a tongue but a hollow cylindrical metal insert allowing electrical connection to a dissipator 80 via the track B− and a screw 1150 corresponding to the orifice 115, the said screw making it possible to compress the said track on the insert and thus to compress the track plus insert on the dissipator so as to effect the earthing of the module, the said dissipator being earthed as will be described in detail below,

the positioning pins 109 situated on the bottom face are positioned differently. A first pin 109 a is positioned as close as possible to the signal tongues 106, and preferentially centred on the middle one, in order to reduce the positioning tolerance of the said tongues with respect to any clearance that may exist between the second pin 109 b and the corresponding orifice 609 b (described in more detail below) of the dissipator bearing. In this way the positioning errors of the tongues with respect to the dissipator are reduced. As illustrated in FIG. 4 b, this first pin 109 a is situated at the middle of the two end signal tongues 106 a. It should be noted that the first pin 109 aserves to position the module along the axis X-Y, and the second 109 b serves to orient the module in terms of rotation and is the furthest away from the tongues 106 a,

one of the protective pins 107 is placed more towards the outside of the module so that there exists a kind of support 119 to make it possible to receive a stay of a signal plate. The pins 107 prevent the signal tongues 106 bending between the time of the manufacture of the module and its assembly on the machine, and serve as preliminary guidance for a signal interconnection piece (described below).

In addition, the module 10 according to this third embodiment also comprises:

an insert 120 comprising a fixing orifice 115, the said insert allowing earthing of the module, and the said orifice being intended to fix the said module to a dissipator by means of screws 1150 for example,

means 126 of electrical protection of the end of the track 103 (B+) that prevent a short-circuit between the potentials B+ (power track of the power interconnection piece) and B− (dissipator mass).

A view without overmoulding of a power module 20 according to this third embodiment is shown in FIG. 4 c.

A view with the “wire bounding” hard-wired connections is shown in FIG. 4 e.

Preferentially, each power module 20 comprises a plate 1022 of low resistance and low thermal conductivity, preferentially made from aluminium (the same resistance as the dissipator) or copper.

Thus there are:

the electronic components 102 welded to the metal tracks,

the metal tracks, which are visible on the bottom face of the housing of the module, are bonded to the plate 1022 by an electrically insulating and thermally conductive adhesive, for example a glass-ball adhesive, the said adhesive electrically insulating the tracks from each other and the tracks with respect to the outside, and

the plate 1022, which is placed on the dissipator.

The plate 1022 is illustrated in FIG. 4 d (representation in cross-section along an axis A-A in FIG. 4 c). It should be noted that this plate can be used in the same way on the other control or excitation modules in the context of visible tracks.

The plate thus makes it possible to test the electrical insulation of each module independently before assembly on the dissipator or dissipator bearing. Thus, if there exists a problem of short-circuit due to faulty application of the insulating adhesive, this plate 1022 avoids the scrapping of all the modules mounted on the dissipator. Only the module posing a problem will be disposed of before it is assembled on the dissipator.

According to a variant of this third embodiment, the module 10 comprises, as illustrated in FIG. 5 a:

a signal connector 116,

a screw 117 a affording electrical contact between two tracks 117 b (+EX, −EX) of a brush holder 50 and the said module 10, and

a screw 117 c for mechanical holding on the dissipator and making it possible to withstand the mechanical forces of the connector 116.

More particularly it is the control module 30 or the control/excitation module that comprises the said connector 116 and the said screw 117 a. It should be noted that the brush holder is here in a single piece with the said module 30. Indeed it is moulded on with the said module.

The presence of the said signal connector 116 has the advantage of:

eliminating welds making it possible to effect electrical connections between the cover and the modules, compared with the first embodiment,

avoiding problems of welding and impermeability,

saving time in the manufacturing process.

There therefore no longer exist any external tongues 106 c as in the first or second embodiments, which makes it possible to reduce the material of the tracks (those in the cover) as will be seen subsequently.

FIG. 5 b is a view from below of the control module 30 according to this third embodiment.

As can be seen, the first positioning pin 109 a is as close as possible to the two series of signal tongues 106 a and 106 b in order to limit any errors in positioning of the tongues with respect to the dissipator.

In addition there can also be seen:

a metal plate 121 fixed by the screw 1150, the said plate preferentially being made from aluminium and thus being connected to the dissipator mass via the said screw 1150, the said plate comprising substrates 123 of the ceramic type, on which electronic components are integrated,

position sensors 122 for giving the position of the stator of the electrical machine.

FIG. 5 c is a view from above of the control/excitation module without overmoulding, without the connector 116 and without the brush holder 50. FIG. 5 d shows the view from below.

FIG. 5 e is a first view without pre-moulding and without overmoulding of the tracks of the control/excitation module in which there can in particular be seen:

a control ceramic 123 comprising the electronic components for controlling the machine, and

an excitation part 124 comprising the electronic components for excitation of the machine via the brush holder 50.

The tracks of the said module can also be seen in the following FIG. 5 f without pre-moulding and without the plastic overmoulding in a view from below.

It should be noted that the pre-moulding is an operation that takes place before the overmoulding and that makes it possible to hold certain elements in position, such as the signal tongues 106 for example.

It should be noted that, in all the embodiments, the electronic components 102, in particular the MOS transistors, are mounted on the power connections, namely here the positive track 103 and the phase track 105.

Preferentially, in all the embodiments presented above, the power tracks of the modules are visible on the bottom face of the modules. It is thus possible to isolate them electrically from the dissipator or dissipator bearing by means of adhesive in place of the plastic of the housing 101. The use of adhesive in place of the plastic of the housing 101 makes it possible to have a lesser thickness under the modules (approximately 0.2 mm in a non-limitative example) and to have a lower thermal resistance than plastic so as to have better dissipation in the dissipator bearing or dissipator.

It should be noted that, in all the embodiments presented above, it is of course possible to include or not the signal connector 116 in the control module or control/excitation module if so desired. If it is not included, it will be in the cover.

It should be noted that the electronic module according to all the embodiments presented above has the following additional advantages:

it uses bare chips for the electronic components instead of so-called packaged standard components, so as to reduce the size,

it includes the elements for controlling the MOS transistors, referred to as drivers,

a module is configured in order to be perfectly integrated on the dissipator or dissipator bearing so that:

it does not block the axis of the bearing in which the shaft of the rotor is introduced, there exists an axial cooling with the attached dissipator (not integrated),

all the ends of the power and signal tracks are outside the circumference of the dissipator or dissipator bearing, which facilitates the connections to be established, unlike the case where they are inside the said circumference, so as to be accessible and so that there exists more space available on the outside diameter than inside for the said ends,

a module is preferentially configured for a single phase so that:

the hook of the module is opposite the natural exit of a stator phase,

there is one module per phase. Thus adaptation to the space available on the dissipator or dissipator bearing is easier compared with a single module comprising three phase tracks, and this in an optimum manner.

the definition of the module makes it possible to have a power, control and excitation module with the same architecture,

in the event of failure of welding of one of the transistors, it avoids too much scrap compared with a single module for the three phases of the stator.

It should be noted that it is also possible to provide a single overmoulding for all the power modules 20, the control module 30 and the excitation module 40 or control/excitation module 30/40.

At this moment there would be a single module that would comprise the power, the control and the excitation, the said module then comprising three phase tracks.

Other Elements

An electronic module 10 cooperates with the following elements:

a dissipator bearing 60 (dissipator integrated in the bearing, i.e. in a single piece with the said bearing), or a dissipator 80 (dissipator not integrated in the bearing, i.e. attached to the bearing)

a signal interconnection piece 22

a power interconnection piece 21, and

a cover 70.

These elements are described below.

Dissipator Bearing

The function of a dissipator bearing is to discharge the heat from the electronic modules.

The rear dissipator bearing 60, shown in FIG. 6, comprises, according to a first non-limitative embodiment:

a plurality of positioning orifices 609, preferentially two 609 a, 609 b per module, in order to position the said modules on the said bearing, the said orifices being situated on the same diameter, i.e. in the example illustrated ten orifices,

a plurality of fixing orifices 608 for receiving the three fixing studs of each module on which the power plate will be positioned, that is to say in the example illustrated fifteen orifices,

air inlets 601 comprising fins 606,

air outlets 602 comprising fins 606,

various recesses referenced 603 for the rotor shaft of the rotary electrical machine, 604 for the Hall effect sensors making it possible to know the rotor position, and 605 for a brush holder 50, and

positioning orifices 610 for positioning a signal plate, here two orifices 610 a and 619 b that are distributed on each side of the diameter of the dissipator bearing. Preferentially one of the orifices is the reference control for the dissipator bearing, and thus an already existing orifice is used.

It should be noted that FIG. 6 shows the locations of the various modules. Thus the locations marked P, c and E receive respectively the three power modules 20, the control module 30 and finally the excitation module 40.

According to a second non-limitative preferential embodiment illustrated in FIG. 7, the dissipator bearing 60 comprises:

a plurality of fixing orifices, here four, 681, 682, 683 and 684 for receiving four studs holding the signal plate,

a fixing orifice 685 for receiving a fixing screw of a brush holder 50, there is no stud, which avoids reducing the cross-section of the track B+ of a power plate,

the following same elements as the first embodiment:

air inlets 601 comprising fins 66,

air outlets 602 comprising fins 606,

various recesses 603, 604 and 605, and

the positioning orifices 610 a and 610 b for the signal plate.

It will be noted that the control and excitation functions have been combined in a single control/excitation module. Moreover, the location C/E and P respectively of the control/excitation module and the power module 20 in FIG. 7 will be noted.

It will also be noted that the fins 606 can, as known to persons skilled in the art, be replaced by a liquid cooling circuit for the two embodiments of the dissipator bearing described above.

Dissipator

The function of the dissipator is to discharge the heat from the electronic modules.

The dissipator 80 as illustrated in plan view in FIG. 8 a is independent of the rear bearing of the rotary machine.

It comprises, according to a non-limitative preferential embodiment:

a base plate 801 preferentially made from cast aluminium, and

fixing orifices 806 on the rear bearing of the machine, here four, in order to receive fixing studs of a signal plate,

an electrical connection orifice 805 for connecting the dissipator to earth via the power interconnection plate by means of a nut,

fixing orifices 804 for fixing the modules, here four, and connecting them to the dissipator earth via an insert,

a fixing orifice 807 for fixing a signal connector of the control/excitation module via an insert,

mechanical positioning orifices 808 for positioning a power plate 21, here two distributed on each side of the diameter of the dissipator,

recesses 809 on the circumference for receiving electrical protection means, here three, for the positive track (B+) of the power interconnection piece,

positioning orifices 810 for the modules, here two per module, that is to say eight orifices,

mechanical positioning orifices 811 for positioning a signal plate 22, here two distributed on each side of the diameter of the dissipator, and

recesses 812 for inserting phase housings of a power plate as will be seen in detail below. There therefore exist three of them here,

recesses 815, 816, 817 for receiving respectively a brush holder, position sensors and the rotor shaft.

The locations C/E and P respectively of the control/excitation module and the power modules 20 will be noted.

FIG. 8 b shows a plan view of the dissipator.

It can be seen that the dissipator also comprises:

blocks of cooling fins 802 intended to substantially increase the heat dissipation of the power modules 20, the said blocks being situated on the bottom face in the position of use of the base plate 801,

support zones 814 for receiving force stays for the power interconnection piece that make it possible to withstand the engine vibrations,

a protrusion 813 that guides the air from the radial inlet of the machine towards the inside of the said machine and thus prevents the air stagnating at the dissipator. This is also the case for the axial air. It is guided towards the inside of the machine. It should be noted that the fins at this level pass through the said protrusion 813. A section X-X of the protrusion can be seen in FIG. 8 c.

In addition, it should be noted that the base plate 801 is configured firstly so as to be able to be assembled in a sandwich between a power interconnection plate and the modules, and a signal interconnection plate, and secondly to leave at the centre a sufficiently large passage for the cooling air of the electrical machine.

As indicated in FIG. 8 d, a first flow of the air will enter the machine in this way axially FA. This has the advantage of increasing the speed of the air and thus reducing the pressure drops compared with a radial flow (the case of the first and second embodiments of the dissipator bearing described previously).

In this way, a looping of air heated by the machine between an output and an input of the dissipator bearing is avoided (for the air incoming axially) and thus re-injecting hot air into the machine is avoided.

More particularly, it is the spacing 817 that is configured so as to allow air to pass around the rotor shaft and is therefore wider than the diameter of the rotor shaft or, to be more precise, of the shaft collector protector.

In this way the standard cooling applied to a conventional alternator is approached.

Moreover, the axial air flow is guided by the first slope 813P1 of the protrusion 813 of the dissipator so that there is no stagnant air on the bottom face of the dissipator level with the fins.

In addition, by virtue of the positioning of the dissipator described, there is also a second air flow that is radial between the dissipator 80 and the power interconnection piece 21. This can also be seen in FIG. 8 d. This radial air FR enters through the dissipator and leaves again through the openings 606 in the bearing. This radial air flow increases the output of air and therefore improves the cooling of the machine, the latter thus being more efficient than if there were only an axial air flow.

In addition, by virtue of the protrusion 813 situated level with the fins, this radial air flow does not stagnate since it is guided by the second slope 813P2 of the said protrusion 813 towards the inside of the machine.

It should be noted that these radial FR and axial FA air flows are accelerated by the fan of the machine, which gives rise to a better cooling of the machine plus the electronics because in particular of the arrangement of the dissipator as described above.

Signal Interconnection Plate

The signal interconnection plate 22 is intended to convey various signals necessary for the functioning of the modules and, thereby, for the correct functioning of the rotary electrical machine. Such signals are for example:

a signal for the operating mode of the electrical machine, for example motor or generator.

a signal indicating the temperature of the modules,

a signal sending back a fault detected on the modules,

a control signal for the switches of the MOSs etc.

These signals are conveyed between the power modules 20 and the control module 30.

FIGS. 9 a to 9 c show a first non-limitative embodiment of the signal interconnection piece 22.

It comprises:

a base plate 220 made from insulating material, preferentially made from plastic, and preferentially substantially cylindrical, which moulds on metal signal tracks TS,

a central recess 223 for lightening the said plate in terms of material,

recesses 221 a for leaving visible metal tracks TS, the said tracks comprising interconnection orifices 2210, here five orifices, the axes of which are disposed in a plane P2 (shown in FIG. 9 c) perpendicular to the surface of the plate and passing substantially through the rotor rotation axis AX, the said orifices being intended to receive the signal tongues 106 of an electronic module with a view to being connected electrically,

a connection recess 221 b for leaving visible metal tracks TS, the said tracks comprising interconnection orifices 2211, disposed at the external periphery of the said plate 22, the said orifices being intended to receive the signal tongues 106 of a control module, here three orifices, and

fixing lugs 222 intended to be inserted in one of the three holding studs 113 of an electronic module, and intended to receive a fixing nut, the said fixing lugs holding the signal interconnection plate 22 on the modules, by means of the studs, first lugs 222 a being disposed on the outside diameter of the said plate and projecting beyond the said plate, and second lugs 222 b being disposed on the internal diameter of the said plate and also attenuating vibrations of the plate.

It should be noted that the recesses 221 a and 221 b can be protected subsequently against the external environment by a resin for example.

It should also be noted that the overmoulding 220 comprises orifices 2210 z, 2211 z opposite the orifices of the metal tracks TS, as illustrated in FIG. 9 b.

The signal plate 22 also comprises:

positioning pins 224 for assembly on a dissipator bearing 60, here two as illustrated on the view from below in FIG. 9 b, and

metal signal tracks TS configured to adapt to the shape of the plate and to the position of the tongues 106 of the modules, and comprising interconnection orifices 2210, 2211 as illustrated in FIG. 9 c. The said tracks are preferentially in the same plane. Moreover, they are preferentially configured in the form of arcs of a circle essentially concentric with respect to the rotor rotation axis.

FIGS. 10 a to 10 c depict a second preferential embodiment of the signal interconnection piece 22.

This signal interconnection plate 22 comprises:

in place of the fixing lugs of the first mode, stays 225 for pressing the modules against a dissipator bearing, first stays 225 a and second stays 225 b being positioned respectively on the external or internal periphery of the said plate, here nine in total; there are thus three support points on each module,

in place of the three recesses per module, only three support inserts 226 intended to receive three studs 226 g, for fixing to the dissipator bearing 60, and

a metal insert 226 for receiving a screw 226 v for fixing the plate to the dissipator bearing. This screw avoids reducing the cross-section of the positive power tracks (B+) of the power interconnection piece 21 (described below).

These four inserts also prevent flow of the overmoulding plastic. It will therefore also be possible to use them for the first embodiment.

The plate 22 also comprises:

at least one fixing housing 227 for fixing the power interconnection piece 21 and receiving a fixing clip (218), here two housings, and

an additional central recess 228 for receiving a brush holder.

In a first variant embodiment of this mode, the plate also comprises separators 229 for signal tongues 106 so as to prevent short-circuits between the said tongues, short-circuits due in particular to salt spray. In this way the length of the electrical path between the tongues is increased.

In another variant, the said plate does not have any separators. At this moment, in order to isolate the said tongues from each other, seals are provides that surround the said tongues 106 on the modules themselves. Subsequently the signal plate 22 will compress these seals.

It should be noted that these two variants apply to the two embodiments of the electronic module described above and to the third embodiment, which will be described later.

In FIG. 10 c, it is possible to see the concentric metal tracks of the signal plate 22. The said metal tracks are configured to adapt to the position of the tongues 106 of the modules, and preferentially to the shape of the said plate, and in addition to pass round the four inserts 226. They are preferentially configured in the form of arcs of a circle essentially concentric with respect to the rotor rotation axis.

It should be noted that the stays 225 are, non-limitatively, cylindrical in shape. This shape has a sharp edge 2250.

In addition, it should be noted that the interconnection plate 22 according to this second embodiment has the following same elements as the plate according to the first mode:

the base plate 220,

the recesses 221 a and 221 b,

the central recess 223 intended to receive here a rotor shaft,

the positioning pins 224, and

the metal tracks TS with the orifices 2210 and 2211.

It should be noted that, for the first and second embodiments described above, the signal tracks are preferentially configured inside the diameter on which the power terminals (described in detail below) are produced. This enables the power plate 21 (described below) to fit on top of the signal plate 22. Thus assembly is facilitated and the said signal tracks do not interfere with the power tracks.

FIGS. 11 a to 11 d depict a third non-limitative embodiment of the signal interconnection piece 22.

It differs from the second embodiment in that:

it no longer has any fixing housings 227 for positioning the power interconnection piece 21 since in this embodiment the power plate 21 is situated below the signal plate 22, as will be seen in detail below.

the stays 225 a and 225 b have a different shape. They have a shape that no longer comprises any sharp edge, which prevents the stresses undergone by the plastic being concentrated on the sharp edges. In this way the risk of breaking the said stays is reduced.

The said signal plate 32 also comprises:

hollowed-out protuberances 230 for pre-positioning the said plate on the said modules. Here there exist two protuberances. They serve in particular for pre-guidance during the process assembly. This thus makes it possible to subsequently fix the positioning pins 224 of the said plate 22 in the dissipator 80. It will thus be possible to position the signal plate 22 before the assembly of the signal tongues 106, and

housings 231 for housing therein filtering capacitors. These capacitors will be connected to the electronic modules. The housings afford good mechanical strength for the said capacitors. Resin will be deposited in the said housings.

Moreover, it should be noted that the interconnection plate 22 according to this third embodiment has the following same elements as the plate according to the second embodiment:

the base plate 220,

the recesses 221 a and 221 b,

the central recess 223,

the recess 228 for the brush holder,

the four inserts 226,

the positioning pins 224, and

the metal tracks TS with the orifices 2210 and 2211.

According to a first variant of this embodiment, the orifices 2210 and 2211 are configured so as to effect a tin weld between the said orifices and the corresponding signal tongues 106. These are therefore holes with a bevel as illustrated in FIG. 11 a and in FIG. 11 b in view from below.

According to a second variant of this embodiment, the orifices 2210 and 2211 are configured so as to effect a laser weld between the said orifices and the corresponding signal tongues 106. These are therefore folded micro-tongues as illustrated in FIG. 11 c.

In FIG. 11 d, the metal tracks of the signal plate 22 can be seen. The said metal tracks are configured so as to adapt to the position of the tongues 106 of the modules, and preferentially to the shape of the said plate, and in addition to pass round the four inserts 226. They are preferentially configured in the form of arcs of a circle essentially concentric with respect to the rotor rotation axis.

Thus, unlike an electronic card for fulfilling the signal function, such a signal plate has the advantages of:

withstanding high temperatures, for example 260° C., unlike a conventional PCB electronic card, such a PCB card being composed of copper tracks with a polymer insulator, the said copper tracks not withstanding high temperatures,

being able to be centred above the electronic modules 10,

comprising metal tracks not necessarily made from copper. This is because, having regard to the relatively low power conveyed by these tracks, a material with a low electrical resistance is not necessarily required. Thus the said tracks can for example, non-limitatively, be made from steel,

be as close as possible to the modules, which avoids having signal tongues for the excessively long modules and thus avoiding problems of plugging in,

by virtue of the metal tracks, which do not overlap, a track cutting is achieved in one go, a fine thickness of the plate is obtained, and therefore a saving in axial size of the whole of the machine, and a facilitated manufacture of the signal interconnection plate.

It should be noted that, naturally, in all the embodiments presented above, it is also possible to provide, instead of the interconnection orifices 2210, 2211, other interconnection means such as folded tongues for example.

Power Interconnection Plate

The power interconnection piece 21 makes it possible to distribute the power between the electronic modules 20, 30, 40 from outside (in particular the vehicle battery).

This piece is independent of the electronic modules, which makes it possible to supply each module with current independently and thus avoid the heating of the modules relating to the passage of the current intended for one module in all the modules. Thus, according to the configuration of this piece and the associated modules, there is no flow of current between the three power modules.

The interconnection piece 21 is, in the most simple case, in the form of a plate produced from an electrically insulating material, preferably plastic.

In a first non-limitative embodiment, illustrated in FIGS. 12 a to 12 c, it comprises:

a central recess 210 for lightening the said plate in terms of material,

power interconnection tracks 211 (−BATT), 212 (+BATT),

negative 2110 and positive 2120 power terminals issuing from the respective power tracks 211, 212,

a plastic overmoulding 213 on the said interconnection tracks 211 and 212,

a first recess 214 a,

a second recess 214 b, and

fixing lugs 215.

The elements of the power interconnection plate are described in detail below.

The power interconnection tracks 211, 212 are disposed at least on one face of the plate. These are tracks made from a metal with low resistance, preferably copper, which are overmoulded in the plastics material of the power plate 21.

They can be produced in the form of a flat strips clipped, riveted, adhesively bonded or fixed in any other suitable manner to the plastic plate.

According to a preferential embodiment, the tracks 211, 212 are interleaved (the track 211 is surrounded by the track 212) and concentric and on the same plane. In this case, the negative power terminals 2110 are folded so as not to interfere with the positive interconnection track 212 (+BATT). In this way, it is possible to optimise the location of the recesses 214 a, 214 b in order to orient a cover according to the requirements of a customer connector making the connection of the machine with the outside. The said tracks 211 and 212 are not superimposed so as to allow electrical connection with the tracks of such a cover, the said zone comprising the recesses 214 a and 214 b.

According to a second embodiment, the tracks 211, 212 can be superimposed on one another. This is beneficial to the radial size.

Finally, it should be noted that each of the power interconnection tracks 211, 212 comprises a hole 217 a, 217 b making it possible to position the said track in terms of x, y in a mould, the latter making it possible to carry out the plastic overmoulding 213.

The power interconnection tracks 211, 212 have respectively negative power terminals 2110 (−BATT) in an L shape, and positive terminals 2120 (+BATT). The said terminals extend radially towards the external periphery of the said piece 21. These terminals have curved free ends. The precise dimensions and position of the terminals 2110, 2120 are determined so as to enable them to be positioned above the ends of the tracks 104, 103 of each of the modules in order to be able to be connected to the said tracks by means of welding, brazing or weld-brazing for example. This configuration of the power terminals (in an L shape and having ends curved by bending) on the outside diameter thus facilitates the assembly with the modules. These terminals thus make it possible to obtain an electrical connection with the corresponding tracks 103, 104 of the electronic modules 10 so that the electrical power is distributed in each of the said modules. It will be noted that the positive power track 212 overlaps the negative interconnection terminals 2110.

The overmoulding 213 comprises a first recess 214 a for an electrical connection of the interconnection track 211, preferably by laser welding, with a cover to the battery, and a second recess 214 b in the said overmoulding for an electrical connection of the interconnection track 212, preferably by laser welding, with a cover to the battery.

Moreover, the overmoulding 213 comprises assembly recesses 216 enabling an assembly tool to pass through the said plate and assemble the rear dissipator bearing with a front bearing.

It should be noted that the ends of the power terminals 2110 and 2120 are not overmoulded so that the said ends can bear on the ends of the tracks 104, 103 of the modules. Preferentially, the whole of the power terminal piece is not overmoulded so that assembly on the ends of the tracks is facilitated. This is because this affords more bending in such an assembly.

The lugs 215 extend substantially radially over the external periphery of the interconnection plate. Each of the lugs 215 is provided with an orifice making it possible to pass therein, when the various modules and the other elements of the arrangement are assembled, fixing means such as threaded rods or bolts or studs or any other suitable fixing element.

In a second non-limitative embodiment, illustrated in FIGS. 13 a to 13 c, the power interconnection plate 21 comprises:

a supplementary central recess 2101,

at least one fixing clip 218,

inserts 219 a, 219 b for receiving holding studs,

a mechanical stop 2112,

at least one support pin 2113, and

an orifice 219 c.

The elements of the power interconnection plate are described in detail below.

The supplementary central recess 2101 allows the insertion of the brush holder with its protector. In this case, the brush cage protector is an independent piece assembled on the brush holder, and the brush holder may be removable with respect to the control/excitation module, which facilitates maintenance of the machine in particular in a replacement context, that is to say when the brushes (and therefore the brush holder) are changed when they are worn. Thus, instead of changing all the electronics (the modules and the two plates), only the brush holder will be changed (if the electronics are not faulty).

The fixing clips 218 enable the plate 21 to be held mechanically on the signal plate 22, here three.

The inserts 219 a and 219 b for receiving the holding studs, here two in total, and for connecting the power tracks 211, 212 to a cover 70. The two inserts 219 a, 219 b make it possible to gain access to the said power tracks so that an overmoulding 213 can be effected on the said tracks as illustrated in FIG. 13 a. These two inserts thus allow mechanical holding of the plate 1 and an electrical connection.

The last orifice 219 c permits solely mechanical holding of the said plate 21 by means of a stud.

The mechanical stop 2112 makes it possible to stop the power plate 21 in translation when it is assembled. It bears, for example, on the control/excitation module. In addition this stop has a shorter length than the power terminals 2110 and 2120 of the power tracks so that the said terminals bear on the tracks of the corresponding modules before the stop bears on the control module. The stop is disposed on the outside diameter of the plate and projects beyond this plate.

The support pins 2113, here two, enable the said plate 21 to bear on the dissipator bearing during assembly.

The plate 21 comprises, as described in the first embodiment:

the central recess 210,

the power tracks 211, 212,

the negative 2110 and positive 2120 power terminals, and

the overmoulding 213.

It should be noted that the overmoulding 213 comprises here a recess 2130 for lightening the plastics material, the said recess being possible since no facing power tracks exist. In the same way as in the first embodiment, the power terminals 2110 and 2120 are not overmoulded.

The power tracks 211 and 212 are shown in FIG. 13 c.

In addition, according to the first and second embodiments:

the plate 21 can also integrate passive filtering components 2114 shown in FIG. 13 b, for example capacitors connected between the power tracks 211 (−BATT), 212 (+BATT) via micro-tongues 21140 a and 21140 b. This makes it possible for example to filter the voltage of the on-board system of the motor vehicle and to filter in particular the oscillations due to the electrical conversion components, MOSs, diodes, etc,

preferentially, the ends of the power tracks are flat and flush on the surface of the module. Thus the advantage of this configuration is being able to weld tracks on a power plate (described in detail below) to the ends of the tracks of a module by flat-on-flat transparency,

the power interconnection plate 21 can also integrate a brush cage protector (not shown) that makes the brush holder impervious. This gives one part less to assemble. The brush holder allows the supply of the excitation current issuing from the excitation module to the rotor via brushes. The said protector then comprises positioning guides that will make it possible to position the said protector opposite the brush holder,

preferentially, the positive terminals 2120 are rigid lugs defining a reference support plane for the said power piece on the corresponding tracks of the modules,

preferentially, the negative power terminals 2110 are flexible lugs for taking into account the assembly tolerances. Thus, when the modules and the said plate are assembled, this will make it possible to deform the tracks of the said power plate before welding by transparency. This thus facilitates putting the power interconnection tracks in contact with the corresponding tracks of the modules. It will be possible to use this flexibility also for the first embodiment, also for the third embodiment described below (although this is not necessary).

FIGS. 14 a to 14 e show a third non-limitative embodiment of the power interconnection piece 21.

The power interconnection plate 21 comprises:

inserts 210 d for establishing a mechanical connection with the rear bearing of the machine,

stator phase protection means 211 d,

means 212 d of positioning on the rear bearing of the machine,

force stays 213 d,

means 214 d of positioning the said plate in the dissipator 80,

a fixing terminal 215 d for fixing the said plate to the dissipator 80,

an electrical insert 216 d,

a power connector 219 d,

positive 221 d (B+) and negative 222 d (B−) tracks moulded on in plastic,

positive power terminals 217 d issuing from the positive track B+,

means 218 d of protecting the positive power terminals 217 d,

a terminal 220 d for mechanical connection to a client power connector (not shown) connected to the battery, and

a mechanical connection orifice 220 e connected to the connection terminal 220 d.

The elements of the power interconnection plate are described in detail below.

The inserts 210 d for establishing a mechanical connection with the rear bearing of the machine, by means of screws for example, here four in total,

the stator phase protection means 211 d are situated on the outside diameter of the said plate and project beyond the plane of the said plate, the said means preventing contact between a stator phase and the dissipator mass or bearing mass in particular,

the means 212 d of positioning on the rear bearing of the machine, the said means being here a positioning pin, extend on the bottom face of the plate, the said pin advantageously being positioned in an oblong hole that is the machining reference orifice of the bearing,

the force stays 213 d allow downward axial deformation of the said power plate in order to avoid vibration problems, the said stays preferentially having a greater height than the inserts 210 d in order to be sure of deforming the plate, the said stays extending over the top face of the plate,

the means 214 d of positioning the said plate in the dissipator 80, here two, extend over the top face of the said plate,

the fixing terminal 215 d makes it possible to fix the said plate to the dissipator 80 by means of a nut, and is connected to the negative power track B−, which effects an earthing of the dissipator,

the electrical insert 216 d is intended to be assembled with the terminal 215 d on the track 222 d, the said track thus being sandwiched by the said insert and the said terminal, which thus avoids difficult welding to be performed between the dissipator, which is preferentially made from cast aluminium, and the copper power track,

the power connector 219 d comprises a negative track B− and a positive track B+,

the power electrical terminals 217 d issuing from a positive track B+ are here in an L shape and have an axial tongue, i.e. perpendicular to the plane of the said plate 21 and projecting beyond the said plane upwards; the said terminals are not overmoulded to allow connection with the end of the positive track 103 (B+) of an electronic module, the terminals extending towards the external periphery of the said piece 22,

the means 218 d of protecting the electrical terminals 217 d protect against short-circuits and salt spray in particular,

the positive 221 d (B+) and negative 222 d (B−) tracks are moulded on in plastic 213 for example, tracks that can be seen in FIG. 14 c. The tracks are visible on the power connector 219 d, which allows the fitting of the client power connector to make the electrical connections between the said connector and the said tracks,

the terminal 220 d connecting to the client connector connected to the battery, the said terminal making it possible to effect a pressing between the tracks 221 d and 222 d and the tracks of the client power connector so that the current can be established correctly between the battery and the machine, and

a mechanical connection orifice 220 e for a screw, thus avoiding the transmission of the mechanical stresses on overmoulding when the client power connector is fixed to the connecting terminal 220 d.

Preferentially, in a variant embodiment, as depicted in FIG. 14 e, the overmoulding 213 of the power plate 21 covers the air outlet openings of the bearing (as far as the outside diameter of the bearing) so as to guide the discharged air in order to reduce a radial looping back of the air towards the inside of the machine. Thus the said overmoulding comprises a covering collar 213 z shown in FIG. 14 e.

Thus the power plate has the advantages of:

having a single track without overlap, the said track making it possible to effect easier moulding and positioning,

being fixed under the dissipator 80 and therefore being separated by a mass from the signal interconnection plate 22, so that the power signal B+ does not interfere with the signals from the said signal interconnection plate 22,

a saving in axial size since the power plate 21 is positioned in the space necessary for the fins of the dissipator,

enabling the dissipator to be an isolated mass (with respect to that of the bearing) or not, and therefore a different mass from that of the bearing, thus avoiding interference of the on-board system during starting in particular.

It will be noted that, by virtue of the presence of the power plate 21, there is a large cross-section of copper for conveying the power necessary to the functioning of the machine (150A in alternator mode, 600A on starting) unlike a solution in which the power tracks are integrated in a band also comprising the electronic power modules.

Cover

According to a first non-limitative embodiment, the cover 70 as illustrated in FIGS. 15 a to 15 c comprises:

positive 71 (B+) and negative 72 (B−) power tracks,

two openings 74 for effecting welding of the tracks 71, 72 with the corresponding tracks of the power plate 21,

signal tracks 75 affording a connection between the modules and signal connections 76,

signal connections 76,

grooves or orifices for positive location 77, and

fixing orifices 78 for fixing screws or nuts for example.

The elements of the cover are described in detail below.

The power tracks 71, 72 are intended to electrically connect the power tracks 212, 211 of the power interconnection piece 21 providing the connection between the client power connector of the motor vehicle. The power tracks 71, 72 are moulded on in the cover 70 and laser welded to the two tracks 212, 211 of the interconnection piece 21. The electrical connections are made between these two elements, for example through the opening 74 provided for this purpose. The electrical connections can be made by welding, in particular by laser welding or weld-brazing, as well as by brazing or by mechanical contact. In the latter case, the mechanical contact is obtained for example by fixing screws for the cover 70 exerting a pressure on the tracks.

The signal connections 76 afford a dialogue with the other electronic boxes of the vehicle. These connections comprise signal tracks 75 integrated in the cover 70 and connected on the one hand to the control module 30 and at the other end to the client signal connector (not shown). The said client signal connector comprises a cable for connection to a control means such as for example a computer controlling various functions of the vehicles such as for example the management of the rotary electrical machine according to its generator or motor functions.

The grooves or orifices for positive location 77 make it possible to position the cover 70 correctly on the guides 107 of the control module 30. The said grooves or orifices thus engage with guides 107 of the control module 30.

According to a second non-limitative preferential embodiment, illustrated in FIG. 16, the cover comprises:

openings 79 intended to receive fixing means such as studs in place of screws.

It also comprises the following elements described in the first embodiment:

the power tracks 71, 72,

the element 73 for connection to the on-board system,

the two openings 74,

the signal interconnection 75,

the signal connections 76, and

the grooves or orifices 77 for positive location.

It should be noted that the cover 70 as described in the two embodiments is intended to be a part specific to each client because of the specific location and the type of client connector or connectors used.

According to a third non-limitative preferential embodiment, illustrated in FIGS. 17 a and 17 b, the cover is a simple cover that comprises solely fixing clips 791 for the cover fitting on studs 226 g of the signal plate 22 fixing the assembly. It no longer comprises any track or connector. There is only plastics material.

After having seen all the elements that cooperate with the electronic modules, we describe below their assembly.

As will be seen in detail below, the electronic modules are fixed to the rear bearing of the machine in several ways:

Either on the bearing directly (dissipator bearing with fins or water integrating or not heat pipes),

or on a non-integrated dissipator (with fins or water integrating or not heat pipes).

1) 1^(st) Method of Assembly or Arrangement

According to a first method of assembling the modules, an electronic module interfaces with the following elements:

a dissipator bearing 60,

a signal interconnection piece 22 according to the first or second embodiments,

a power interconnection piece 21 according to the first or second embodiments,

a cover 70 according to the first or second embodiments.

Thus the 1^(st) method of assembling all the parts described above is effected in the following manner.

In a first step 1), the electronic module or modules are mounted on the dissipator bearing 60.

The positioning of each module on the dissipator bearing 60 is facilitated by the two positioning pins 109 a, 109 b, which will be situated opposite each orifice 609 a, 609 b of the corresponding bearing 60.

The modules are fixed to the dissipator bearing 60 on the one hand by means of an adhesive, for example with glass balls, and on the other hand mechanically in two different ways.

According to a first non-limitative way, illustrated in FIG. 18, each of the modules is fixed by three studs 113. The three studs are inserted in the corresponding orifices 608 in the said bearing. FIG. 18 shows the assembly of five modules, three power modules 20, a control module 30 and an excitation module 40.

According to a second non-limitative preferential way, illustrated in FIG. 24, the fixing is effected by means of:

three studs 226 g that are put in place after the installation of the signal interconnection plate 22 and that are inserted in the corresponding orifices 681, 682, 683 in the dissipator bearing 60, and

a screw 226 v that is inserted in the associated orifice 684 in the bearing.

FIG. 23 shows the assembly of four modules, three power modules 10, one control/excitation module.

For the two ways, all the modules are preferentially arranged in the same plane perpendicular to the rotation axis of the rotor of the electrical machine, just like the power tracks and the signal connections, in order to facilitate their assembly.

However, in a variant of what is presented in the previous figures, the modules can be disposed on different planes.

In a second step 2), the signal interconnection plate 22 is mounted on the electronic modules. Because of this, the said plate is as close as possible to the modules in order to reduce the length of the signal connections as far as possible and to prevent plugging problems. In this way, the signal connections 106 of the modules are short; thus their deformation is better controlled (they are less deformable), the said connections preferably being flexible.

The signal interconnection plate 22 is fixed to the module/bearing assembly in two different ways corresponding to the two ways of fixing the modules to the bearing as described previously.

According to a first non-limitative way, illustrated in FIG. 19, the plate 22 is positioned by means of the positioning studs 224, which are positioned opposite the positioning orifices 601 a and 601 b of the bearing. Thus, by virtue of this positioning:

the connection recesses 221 a are placed opposite the signal connection elements 106 a of the modules,

the connection recesses 221 b are placed opposite the signal connection elements 106 b of the modules, and

the fixing lugs 222 are placed opposite the studs 113 of the modules 10.

Next, after pressing, the signal connections 106 a are inserted in the interconnection orifices 2210 of the metal signal tracks TS, the connection elements 106 b are inserted in the interconnection orifices 2211 of the metal signal tracks TS, and the lugs 222 are fixed to the studs 113.

According to a second non-limitative preferential way, illustrated in FIG. 24, the plate 22 is positioned on the modules by means of the positioning pins 224, which are positioned opposite the positioning orifices 610 a and 610 b of the bearing. Thus, by virtue of this positioning:

the connection recesses 221 a are placed opposite the signal connection elements 106 a of the modules,

the connection recesses 221 b are placed opposite the signal connection elements 106 b of the modules,

the stays 225 a and 225 b are placed opposite the support zones 114 of the modules, and

the inserts 226 are placed opposite the corresponding orifices 681 to 684 in the bearing.

Next, after pressing, the connection elements 106 are inserted in the said corresponding recesses 221, the stays 225 bearing on the support zones 114 of the modules.

The studs 226 g, which are inserted in the orifices 224 in the said plate 22 and 681, 682, 683 of the dissipator bearing 60, are then fixed. The studs bear on the said plate and consequently on the plate/modules/bearing assembly so as to afford better mechanical strength. In the same way, the screw 226 v is screwed into the respective corresponding orifices 226 and 684 in the plate 22 and bearing 60.

Thus the signal interconnection plate 22 is produced so as to exert a pressure on the power modules 20 and the other modules 30, 40 in order to guarantee their holding throughout the life of the rotary electrical machine.

In a non-limitative embodiment, the material of the said plate is PPS (phenylene polysulphide) plastic containing glass fibres.

Thus, according to these two ways, the signal plate is deformed in order to exert a pressure on the modules, the deformation preferably being approximately 0.3 mm. In this way, the detachment of the modules is prevented and stresses on the welds of the tongues are avoided.

In a third step 3), the power interconnection plate 21 is mounted on the bearing/modules/signal plate assembly. The power interconnection plate 21 is fixed above the signal interconnection plate 22.

The power plate 21 is fixed in two different ways.

According to a first non-limitative way, illustrated in FIG. 20, the power plate 21 is placed on the signal plate 22 so that:

the fixing lugs 215 are placed opposite the studs 113 of the modules 22, the said studs making it possible to position the said plate 21,

the power terminals 2120, 2110 are placed opposite the corresponding tracks of the module 103, 104,

In the case of a brush holder, it is positioned so that it is inserted in the recess 605 and the brush cage protector in the recess 603 of the bearing.

Next, after pressing, the fixing lugs 215 are fixed on the studs 113, the power terminals 2120, 2110 bear respectively on the ends of the tracks 103,104 of the modules.

According to a second non-limitative preferential way, illustrated in FIG. 25, the power plate 21 is placed on the signal plate 22 so that:

the inserts 219 are placed opposite the studs 226 g, the said orifices and studs serving as a positive location device,

the lug 218 is placed opposite the holding clip 227 of the signal plate 22.

Next, after pressing, the orifices 219 are inserted on the studs 226 g and the lug 218 snaps in the clip 227, and

the orifice 219 c is placed opposite a third stud 226 g.

In a last step, the cover 70 is mounted on the assembly. In this way, the cover 70 forms a shroud for the rear bearing of the machine.

The cover 70 is fixed in two different ways.

According to a first non-limitative way, illustrated in FIGS. 21 and 22, the cover 70 is placed on the power plate 21 so that the grooves 77 of the cover are situated opposite the guides 107 of the control module 30. These guides and grooves serve as a positive location device.

Next, after pressing, the said grooves are inserted in the said guides so that:

contact is established between the signal tracks 75 of the cover 70 and the tongues 106 c of the control module 30, and

contact is established between the power tracks 71 (B+), 72 (B−) of the cover and respectively the power tracks 212, 211 of the power plate 21.

Finally, after installation of the cover, the electrical connection is made between the tracks 71, 72 of the cover and the tracks 212, 211 by laser welding via the openings 74.

The cover is fixed by three screws or nuts 78.

According to a second non-limitative preferential way, illustrated in FIG. 26, the cover 70 is placed on the power plate 21 in the same way as the first way with a view to establishing the electrical contacts. In addition, the openings 79 are placed above the three studs 226 g that fix the electronic assembly.

Next, after pressing, the cover 70 is fixed by means of the said studs to the electronic assembly (bearing/modules/interconnection plates).

In this case, the cover 70 bears on all the elements of the arrangement and thus ensures sufficiently strong support in order both to immobilise the power plate 21 on the dissipator bearing and to provide the necessary electrical contacts.

Thus, as can be seen, according to this first assembly mode, the electronic modules 10, the signal interconnection piece 22, the power interconnection piece 21 and the dissipator occupy respectively first, second, third and fourth planes all parallel to one another, and the planes are superimposed in the following order starting from the plane closest to the rear bearing of the machine:

fourth plane,

first plane,

second plane, and

third plane.

Thus the power interconnection piece 21 is independent of the electronic modules and is connected to the said modules in particular only by its power electrical terminals.

The same applies to the signal interconnection piece 22, which is connected to the said modules in particular only by its signal connections 106.

2) 2^(nd) Assembly Mode or Arrangement

According to a second module assembly mode, or arrangement, an electronic module interfaces with the following elements:

a dissipator 80,

a signal interconnection piece 22 according to the third embodiment,

a power interconnection piece 21 according to the third embodiment,

a cover 70, according to the third embodiment.

Thus the second method of assembling all the parts described above is effected as follows.

It should be noted that, in the example taken for this assembly method, there exist four modules that are fixed to the dissipator 80. Three power modules 20 and one control/excitation module 30.

In a first step 1), illustrated in FIG. 27 a, the modules are positioned on the top face of the dissipator 80 so as to fix them.

The positioning takes place by means of the positioning pins 109 a and 109 b, which are placed opposite the orifices 810 of the dissipator 80, and during the positioning the insert 120 of each module comes to be positioned opposite each associated orifice 804 in the dissipator 80.

Subsequently the fixing is carried out by means of:

screws 1150 that are inserted in the fixing orifices 115 of the modules and the corresponding orifices 804 of the dissipator 80. These fixing screws also make it possible to connect the modules to earth via the insert 120, and

the connector 116 of the control/excitation module 30, which is screwed into the associated orifice 807 of the dissipator, by means of a via screw.

During assembly,

the electrical protection means 126 of the modules are inserted in the recesses 109 of the dissipator provided for this purpose.

In addition, the modules are also bonded to the dissipator 80 by means of an adhesive, such as a glass ball adhesive.

It should be noted that, prior to the fixing of the control/excitation module 30 to the dissipator 80, the brush holder 50 was fixed to the said module by means of the screw 117 a provided for this purpose. In another variant, it is possible to fix it after the installation of the said module 30 on the dissipator 80.

In a second step 2), illustrated in FIG. 28, the power plate 21 is positioned on the bottom face of the dissipator so as to fix the said plate 21 to the said dissipator 80.

The positioning is effected by means of:

means 214 d of positioning the said plate 21 that come opposite the associated positioning orifices 808 in the dissipator, and

the fixing terminal 215 d, which comes opposite the electrical connection orifice 805.

The fixing of the said plate 21 on the dissipator 80 is effected by means of:

the two positioning means 214, which are placed in the corresponding orifices 808 in the dissipator,

the fixing terminal 215 d, which is plugged into the electrical connection orifice 805, and

the four force stays 213 d, which are placed opposite the corresponding supports 814 of the dissipator.

During assembly,

phase protection means 21 ld are integrated in the recesses 812 provided for this purpose in the dissipator.

Thus, as can be seen in FIG. 28:

the means 221 d will protect the phase tongues of the stator,

the axial tongues of the electrical terminals 215 d are then opposite the corresponding positive tracks 103 (B+) of each electronic module 10, which will make it possible to establish an electrical connection between the said tracks 103 and the positive track 221 d (B+) of the power plate 21, and

the electrical insert 216 d integrated in the terminal 215 d makes it possible to earth the dissipator 80.

In a third step 3), illustrated in FIG. 29, the signal interconnection plate 22 is positioned on the said electronic modules 10 so as to fix it.

It should be noted that the signal plate 22 is pre-positioned (pre-guided) by virtue of two protection pins 107 of two electronic modules 10, the said pins being the furthest away from each other in order to preguide well.

The positioning is effected by means of:

the two hollowed-out protuberances 230 serving for pre-guidance and which are pre-positioned on two positioning pins or guides 107 belonging to electronic modules.

Then, subsequently, it is possible to position the signal plate 22 by means of the positioning pins 224 in the corresponding orifices 811 of the dissipator 80.

During assembly, there are:

the connection recesses 221 a that are placed opposite the signal connection elements 106 a of the modules,

the connection recesses 221 b that are placed opposite the signal connection elements 106 b of the modules,

the stays 225 a and 225 b that are placed opposite the support zones 119, 114 respectively of the modules, and

the inserts 226 that are placed opposite the corresponding orifices 806 of the dissipator.

The fixing takes place by means of:

insulated hollow rivets 2101 d associated with the inserts 210 d of the power plate. These rivets 2101 d inside the inserts allow on the one hand an assembly of the signal plate and on the other hand an insulation of the mass of the dissipator with respect to the mass of the bearing, and finally the creation of an electronic sub-assembly (the two plates, the dissipator and the electronic modules) pre-assembled so that, during assembly on the bearing, by means of screws or studs, after welding the signal connections 106 with the signal plate 22, there are no additional forces that would risk mechanically stressing the said welds.

Next, after pressing, the signal tongues 106 are inserted in the said corresponding interconnection orifices 2210, 2211, the stays 225 bearing on the support zones 119, 114 of the modules.

It should also be noted that the housings 231 of the signal plate comprise in the example illustrated in FIG. 29 a capacitor associated with each of the power modules 20, which is connected firstly to the positive track 103 (B+) of the associated module and secondly to the negative track 104 (B−) of the said associated module.

In addition, preferentially, it is possible to effect a tin or laser welding, or to deposit a resin plus polymerisation in the connection recesses 221 a and 221 b of the signal tongues 106 in order in particular to protect them from salt spray.

In a fourth step 4), illustrated in FIG. 30 a, the whole of the electronics thus obtained are positioned on the rear bearing 90 of the machine.

Fixing takes place by means of:

four studs 226 g or screws in the rear bearing 90 by means of the inserts 226 of the signal plate 22, 210 d of the power plate 21 and 806 of the corresponding dissipator 80. The studs bear on the same plate and consequently on the plate/dissipator/bearing assembly so as to create an electronic assembly on the bearing. In the same way, the screw 226 v is screwed in the respective corresponding orifices 226 and 807 of the plate 22 and dissipator 80.

FIG. 30 b is a view in section along the plane X-Y shown in FIG. 30, showing an entire assembly of the main parts cited above. It shows in particular:

the bearing 90,

the signal interconnection plate 21,

the dissipator 80,

the signal interconnection plate 22,

a rivet 210 ld, and

a fixing stud 226 g.

It should be noted that, prior to the electronic assembly, the rear bearing 90 of the machine is fixed to the front bearing (not shown) of the said machine by means of four tie rods in orifices 903, the orifices being illustrated in FIG. 30 c of the bearing 90. The tie rods are thus screwed before the electronic assembly, which makes it possible to position the phases of the stator in advance and therefore to facilitate the assembly of the electronic sub-assembly with the said phases.

The rear bearing comprises in particular:

a positioning orifice 901 configured so as to receive the positioning pin 1151 of the control/excitation module 30, which allows precise positioning of the position sensors with respect to the bearing, and

a referencing orifice 902 in which the pin 212 d of the power plate 21 is inserted.

The phase hooks 105 cr are also welded to the phases of the stator (standard wires or using a thimble).

Finally, in a fifth step 5), the plastic cover 70 is put in place by means of fixing clips that are snapped onto the studs.

It should be noted that the steps specified above can be performed in a different order. For example, the second step can of course be performed before the first step (FIG. 27 b illustrates this case) or after the third step.

Thus the second assembly method has the following advantages:

Firstly, the assembly of the entire electronic part (modules, power and signal plates) takes place outside the rear bearing so that it is possible to test the electronics before assembly on the machine; in this way only the electronics that function in the said machine are integrated, which saves time in terms of process, and makes it possible to have two independent processes and therefore not to modify the “process” method of standard machine assembly that already exists;

Secondly, the assembly of the electronic part can take place after the assembly of the rear bearing of the machine on the front bearing, or more particularly after the fitting of the tie rods fixing the bearings, which will then be covered by the electronics;

Thirdly, the performance with regard to thermal cooling is improved because of the axial air flow added to the radial air flow. There is a reduction in pressure drops with an axial air inlet;

Fourthly, the cover is now no more than a simple plastic cover. There are no moulded-on tracks in the cover, the power tracks and the signal tracks being integrated respectively in the power plate and in the control/excitation module, which makes it possible to limit the number of interconnection welds to be carried out;

Fifthly, the earth plane is implemented by the dissipator. There is therefore a reduction in the resistance and inductance of the internal power circuit between the client two-phase power connector and the power module because of the proximity of the positive-polarity track (B+) of the power plate (21) to the dissipator mass;

Sixthly, the earth plane is implemented by the dissipator, so that there is a saving in axial space. In this way an existing part is used for conveying current.

Thus, according to this second assembly method, the electronic modules 10, the signal interconnection piece 22, the power interconnection piece 21 and the dissipator occupy respectively first, second, third and fourth planes all parallel to one another, and the planes are superimposed in the following order, starting from the plane closest to the rear bearing:

third plane,

fourth plane,

first plane, and

second plane.

Thus the power interconnection piece 21 is independent of the electronic modules and is connected to the said modules in particular only by its electrical power terminals.

The same applies to the signal interconnection piece 22, which is connected to the said modules in particular only by its signal connections 106.

Thus all the four parts form an independent electronic sub-assembly of a bearing of the machine.

It should be noted that the two assembly methods have the advantage of using the maximum surface available on the rear of the machine for the modules by virtue of the stacking of the various elements for the power and signal interconnections, unlike a solution in which the power and signal interconnection tracks occupy surface on the rear of the machine to the detriment of the modules.

It should be noted that the signal interconnection plate 22 according to the various embodiments described above can be used when there is no power plate 21. For example with modules themselves effecting their power interconnection.

As for the power interconnection plate 21 according to the various embodiments described previously, it can also be used without the signal plate 22. For example, with an electronic card PCB effecting the signal interconnection.

The assembly according to all the embodiments presented above has the following additional advantages:

it avoids stacking all the tracks on one another, a stack not being propitious to good holding in position of the tracks,

it comprises means of fixing to the dissipator or to the dissipator bearing that are not concentrated on the periphery of the said dissipator or bearing, so that there exists a distribution of forces so as to withstand the mechanical vibrations well,

it enables the various components (interconnection plates and modules) to be in different planes and perpendicular to the rotation axis of the machine, so that it creates more space for the power tracks, which gives rise to a reduction in the resistivity of the said tracks. Thus this assembly makes it possible to convey higher power,

it makes it possible to use in an optimum fashion the space available for the electronic modules on the rear bearing of the machine, the various components (interconnection plates and modules) being on different planes and perpendicular to the rotation axis of the machine. 

1. A dissipator for discharging heat from electronic components, the electronic components being intended for the functioning of a rotary electrical machine, the rotary electrical machine comprising a rear bearing, said dissipator comprising a top face and a bottom face integrating fins, wherein the dissipator is disposed between the rear bearing of the rotary electric machine and said electronic components, said bottom face integrating said fins coming opposite said rear bearing when said dissipator is disposed between the rear bearing of the rotary electrical machine and said electronic components.
 2. The dissipator according to claim 1, which also comprises a protrusion on its bottom face level with the fins.
 3. The dissipator according to claim 1, wherein the protrusion comprises a first slope for guiding an axial air flow towards the inside of the machine, and a second slope for guiding a radial air flow towards the inside of the machine.
 4. The dissipator according to claim 1, which comprises a spacing configured so as to allow air to pass around the rotor shaft of the machine.
 5. The dissipator according to claim 1, wherein the spacing is greater than the diameter of the rotor shaft.
 6. The dissipator according to claim 1, wherein a power interconnection piece is placed on the bottom face of the dissipator, said power piece distributing power to said module.
 7. The dissipator according to claim 1, which comprises positioning devices for said power interconnection piece.
 8. The dissipator according to claim 1, wherein at least one electronic module comprising electronic components is mounted on the top face of said dissipator.
 9. The dissipator according to claim 1, which comprises positioning devices for said electronic modules.
 10. The dissipator according to claim 8, wherein a signal interconnection piece is mounted on said electronic module, said signal interconnection piece being intended to convey control signals between electronic components.
 11. The dissipator according to claim 1, which comprises positioning devices for said signal interconnection piece.
 12. The dissipator according to claim 1, wherein it is attached.
 13. A rotary electrical machine comprising: a dissipator for discharging heat from electronic components, said dissipator comprising a top face and a bottom face integrating fins; an electric motor; and a rear bearing; wherein said dissipator is disposed between said rear bearing of the rotary electric machine and the electronic components, said bottom face integrating said fins coming opposite said rear bearing when said dissipator is disposed between the rear bearing of the rotary electrical machine and said electronic components.
 14. The dissipator according to claim 13, which also comprises a protrusion on its bottom face level with the fins.
 15. The dissipator according to claim 13, wherein the protrusion comprises a first slope for guiding an axial air flow towards the inside of the machine, and a second slope for guiding a radial air flow towards the inside of the machine.
 16. The dissipator according to claim 13, which comprises a spacing configured so as to allow air to pass around the rotor shaft of the machine.
 17. The dissipator according to claim 13, wherein the spacing is greater than the diameter of the rotor shaft.
 18. The dissipator according to claim 13, wherein a power interconnection piece is placed on the bottom face of the dissipator, said power piece distributing power to said module.
 19. The dissipator according to claim 13, which comprises positioning devices for said power interconnection piece.
 20. The dissipator according to claim 13, wherein at least one electronic module comprising electronic components is mounted on the top face of said dissipator. 